diff --git a/CHANGELOG.md b/CHANGELOG.md
index 19c5b5d..4ef6033 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Change Log
 
+## [v4.21.0](https://github.com/plivo/plivo-node/tree/v4.21.0) (2021-07-20)
+- This version includes advancements to the Messaging Interface that deals with the [Send SMS/MMS](https://www.plivo.com/docs/sms/api/message#send-a-message) interface, Creating a standard structure for `request/input` arguments to make implementation easier and incorporating support for the older interface.
+
 ## [v4.20.0](https://github.com/plivo/plivo-node/tree/v4.20.0) (2021-07-13)
 - Power pack ID has been included to the response for the [list all messages API](https://www.plivo.com/docs/sms/api/message/list-all-messages/) and the [get message details API](https://www.plivo.com/docs/sms/api/message#retrieve-a-message).
 - Support for filtering messages by Power pack ID has been added to the [list all messages API](https://www.plivo.com/docs/sms/api/message#list-all-messages).
diff --git a/package.json b/package.json
index d429fd9..a471bda 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "plivo",
-  "version": "4.20.0",
+  "version": "4.21.0",
   "description": "A Node.js SDK to make voice calls and send SMS using Plivo and to generate Plivo XML",
   "homepage": "https://github.com/plivo/plivo-node",
   "files": [